Abstract: A method for improving the endurance of a blade base (6) of the disc (1) of a disc chipper, a blade base and a disc chipper. A wearing plate (10) is attached to the surface (18) of the blade base facing towards the chip opening (7), the wearing surface (10) of which is shot peened.

Abstract: A method of making a shock-resistant and wear-resistant composite steel tool comprises providing a steel tool body having a working edge, and providing a working part material of nonporous wrought steel in an unhardened state which is hardenable to a hardness greater than that of the body. The working part material, in its unhardened state, is fused by welding to the working edge of the tool body while being pressed forcibly against the working edge. After the fusion step, the outer surface of the working part material is hardened to a hardness greater than that of the body of the tool, the depth of penetration of such hardening being limited to the region immediately adjoining the outer surface of the material so that the underlying region of the working part remains ductile, and the weld is normalized thereby increasing its ductility and resultant shock resistance.

Abstract: A bandsaw blade comprises a plurality of cutting teeth spaced longitudinally apart by gullets. Each tooth includes a steel portion and a carbide tip brazed to a front face of the steel portion. The deepest point of the gullet lies on a curved section having a relatively large radius of curvature, and is spaced longitudinally forwardly of the trailing carbide tip by a relatively large distance. Transversely spaced corners of the gullet bottom are made smoothly rounded by a shot-peening operation.

Abstract: A press plate hardened by the use of plasma ion nitriding techniques produces wear resistant decorative laminate containing hard abrasive particles while improving associated press plate useful life. The press plate has exacting final microfinish requirements made possible due to the determination of interdependencies between parameter settings and expected results. These interdependencies include the work piece geometry, surface and subsurface structure and desired results, process temperatures, pressures, and rate of heat-up and duration of heat-up time, thermal loading, reflective radiation and heat effects, cooling systems, and gas mixture composition.

Abstract: A cutting tool is disclosed which has a tool body, a cutting insert and an insert-holding member. The tool body has a recess formed therein, and the cutting insert is received in the recess. The insert-holding member is attached to releasably secure the cutting insert to the recess. The insert-holding member includes a surface layer having a thickness of 0.1 to 1.0 mm and an interior portion. The surface layer is harder than the interior portion and has a hardness of from H.sub.R C 40 to 60.

Abstract: An apparatus for unnailing wood pallets includes a frame, a first cutter assembly and a second cutter assembly positioned vertically above the first. The first cutter assembly includes a pair of elongated horizontal support arms supporting a cutting head at one end, downwardly biasing springs at an opposite end and a pivot between the ends. The second cutter assembly includes a pair of elongated horizontal support arms supporting a second cutting head at one end and a pivot at an opposite end that is coaxial the pivot of the first cutter assembly. The second cutter assembly is biased upwardly by springs between its support arms and those of the first cutter assembly. A stringer return member is horizontally movable with a pallet-moving cradle and includes a member which is pivotally mounted to the cradle at one end and has a follower at an opposite end to follow a track that moves with the support arms in order to keep the member positioned between the pair of support arms.

Abstract: A roller cutter (28) for a rotary drill bit (10) and method of making, utilizing an ion nitriding hardening process for the external surface (42) and the internal bearing surfaces (33, 34, 38) in the central cavity (30) of the roller cutter (28). The roller cutter (28) is made from a through hardenable steel and the ion nitrided hardened layer (77) has a total thickness less than around 0.030 inch. Hardened layer (77) has a relatively thick inner stratum (80) and a relatively thin outer surface stratum (78). The outer stratum (78) is formed of Fe.sub.4 N having a thickness no greater than around 0.0004 inch to form an outer surface which is ductile and has a relatively low friction coefficient.

Abstract: A rock drilling bit comprises a steel body defining a cutting face with hard material inserts press-fitted into preformed openings in the cutting face. The inserts have ends extending outwardly of the cutting face which perform the actual drilling or cutting operation. The face surface of the body is case hardened except for narrow continuous bands about each insert opening. A method particularly suited for forming the case hardened cutting face is also disclosed.

Abstract: A cutting and scoring line consisting of a blade (1) of steel with a cut bevel (2) formed on one longitudinal side of the blade, and the blade (1) is hardened in the area of the bevel (2) and the bevel has a fine grind (5) in the hardened area (4) starting from the tip (3) of the bevel.

Abstract: Bearing surfaces or other selected areas of component parts of a rotary cone earth boring rockbit are carburized or otherwise surface enriched by the sequential steps of coating the selected surface area to be enriched with a non-water based composition capable of effecting a corrosive protective seal thereabout; covering the coated area with a predetermined applied thickness of a carbonaceous paste; drying the paste and thereafter, subjecting the component part to an elevated temperature below which the coating is pyrolyzed to fully austenize the part and achieve a desired case depth followed by quenching, tempering, and finished machining as required.

Abstract: A rotary cutting tool for processing a metal workpiece includes an elongated solid body composed of cemented carbide containing cobalt. The body has cutting edge means at its forward end and an axis of rotation therethrough. The body has a surface of which cobalt content is greater than that of the remainder of the body. Part of the surface of the body is ground to remove the cobalt-rich surface therefrom.

Abstract: A coated steel product, namely, a cutting instrument such as a band saw blade, in which the body of the blade is of steel, the tooth tip is of impulse hardened steel and the tip is covered with a coating of titanium carbide or refractory metal carbide, the coating metal or compound having been deposited by ion plating onto the surface of the tip. The process through which the cutting tool is produced includes preshaping and sharpening the tool, then ion cleaning the tips, bombarding the tips with ions of the titanium or refractory metal followed by reacting the titanium or refractory metal with a carbon containing chemical or their carbides and then simultaneously subjecting both the coating and the steel tip to a magnetic flux for impulse hardening primarily the steel tip. Other coatings of metal carbides, nitrides, borides and metal compounds are described.